Thanks for the reply Zeromus,
I only had a few hours in total to create this and I had so many ideas :D
The retry butotn seems to be a WebGL issue only, I'm assuming one of the other UI layers is overlapping, so I'll reorder the button to the top :)
I'll create custom character sprites to add more life to the game as well as music and sound effects.
Some other improvements I'm looking at are SFX when the player collides with the floor, walls etc.
Thank you so much for hte feedback, hopefully I'll turn this into an amainz little game.